Fix a bug where calibrations are not added to RB circuit for 3q custo…

…m pulse gates

qiskit_experiments/library/randomized_benchmarking/standard_rb.py

@@ -379,10 +379,8 @@ def _transpiled_circuits(self) -> List[QuantumCircuit]:
             ]
             # Set custom calibrations provided in backend
             if isinstance(self.backend, BackendV2):
-                qargs_patterns = []
-                if self.num_qubits == 1:
-                    qargs_patterns = [self.physical_qubits]
-                elif self.num_qubits == 2:
+                qargs_patterns = [self.physical_qubits]  # for 1q or 3q+ case
+                if self.num_qubits == 2:
                     qargs_patterns = [
                         (self.physical_qubits[0],),
                         (self.physical_qubits[1],),

test/library/randomized_benchmarking/test_interleaved_rb.py

@@ -16,10 +16,12 @@
 from test.library.randomized_benchmarking.mixin import RBTestMixin
 from ddt import ddt, data, unpack
 
+from qiskit import pulse
 from qiskit.circuit import Delay, QuantumCircuit, Parameter, Gate
 from qiskit.circuit.library import SXGate, CXGate, TGate, CZGate
 from qiskit.exceptions import QiskitError
 from qiskit.providers.fake_provider import FakeManila, FakeManilaV2, FakeWashington
+from qiskit.transpiler import InstructionProperties
 from qiskit_aer import AerSimulator
 from qiskit_aer.noise import NoiseModel, depolarizing_error
 from qiskit_experiments.library import randomized_benchmarking as rb
@@ -281,6 +283,30 @@ def test_interleaving_cnot_gate_with_non_supported_direction(self):
         with self.assertRaises(QiskitError):
             exp.circuits()
 
+    def test_interleaving_three_qubit_gate_with_calibration(self):
+        """Test if circuits for 3Q InterleavedRB contain custom calibrations supplied via target."""
+        my_backend = FakeManilaV2()
+        with pulse.build(my_backend) as custom_3q_sched:  # meaningless schedule
+            pulse.play(pulse.GaussianSquare(1600, 0.2, 64, 1300), pulse.drive_channel(0))
+
+        physical_qubits = (2, 1, 3)
+        custom_3q_gate = self.ThreeQubitGate()
+        my_backend.target.add_instruction(
+            custom_3q_gate, {physical_qubits: InstructionProperties(calibration=custom_3q_sched)}
+        )
+
+        exp = rb.InterleavedRB(
+            interleaved_element=custom_3q_gate,
+            physical_qubits=physical_qubits,
+            lengths=[3],
+            num_samples=1,
+            backend=my_backend,
+            seed=1234,
+        )
+        circuits = exp._transpiled_circuits()
+        qubits = tuple(circuits[0].qubits[q] for q in physical_qubits)
+        self.assertTrue(circuits[0].has_calibration_for((custom_3q_gate, qubits, [])))
+
 
 class TestRunInterleavedRB(QiskitExperimentsTestCase, RBTestMixin):
     """Test for running InterleavedRB."""